Dr. Edmond Locard (13 Dec. 1877-4 May 1966) formulated Locard's principle which states that the perpetrator of a crime will bring something into the crime scene and leave with something from it, and that both can be used as forensic evidence. That is there is a contact transfer between the perpetrator and the crime scene. This contact transfer is the basis for much of Forensic Science. In many cases what the perpetrator brings and leaves is their fingerprint, more specifically a representation that is made up of chemicals from the perpetrator's body. The visual record of a fingerprint is frequently used by forensic chemists to identify individuals who might have been present at a crime scene.